嗜热链球菌抑制法测定鲜乳中抗生素残留检验方法的优化

Optimization of Antibiotic Residues in Fresh Milk by Streptococcus thermophilus

目的:对国标嗜热链球菌抑制法测定鲜乳中抗生素残留的检验方法进行验证并优化,建立优化后的实验室检验方法。方法:按照《食品卫生微生物学检验鲜乳中抗生素残留检验》(GB/T 4789.27—2008)中嗜热链球菌抑制法进行抗生素检测。结果:按照国标方法检验,测试菌液加1 mL时,常见抗生素的最低检出限分别为青霉素30μg·L^(-1)、链霉素5 000μg·L^(-1)、庆大霉素3 000μg·L^(-1)、卡那霉素5 000μg·L^(-1)。当添加测试菌液量减少为100μL时,常见抗生素的最低检出限分别为青霉素3.0μg·L^(-1)、链霉素50μg·L^(-1)、庆大霉素30μg·L^(-1)、卡那霉素50μg·L^(-1)。结论:标准方法的灵敏度低,可以通过减少嗜热链球菌的添加量来提高该检验方法的灵敏度。

Objective:To validate and optimize the national standard Streptococcus thermophilus inhibition method for the determination of antibiotic residues in fresh milk,and to establish the optimized laboratory test method.Method:Antibiotics were detected according to the suppression method of Streptococcus thermophilus in GB/T 4789.27—2008.Result:According to the national standard method,when testing the bacterial solution with 1 mL,the lowest detection limits of common antibiotics were penicillin 30μg·L^(-1),streptomycin 5000μg·L^(-1),gentamicin 3000μg·L^(-1),kanamycin 5000μg·L^(-1).When the amount of added bacteria was reduced to 100μL,the lowest detection limits of common antibiotics were penicillin 3.0μg·L^(-1),streptomycin 50μg·L^(-1),gentamicin 30μg·L^(-1) and kanamycin 50μg·L^(-1),respectively.Conclusion:The sensitivity of standard method is low,and the sensitivity of this test can be improved by reducing the amount of Streptococcus thermophilus.